SEKOIA_Loader_Win_Revil_Loader

import "pe"
import "hash"

rule SEKOIA_Loader_Win_Revil_Loader
{
	meta:
		description = "Detect the REvil loader using DDL side loading. The detected ressource is a legitimate executable used to load the malicious .dll containing the ransomware"
		author = "Sekoia.io"
		id = "3c293e87-e2d7-475a-9536-8b991961fa11"
		date = "2021-07-19"
		modified = "2024-12-19"
		reference = "https://www.mcafee.com/blogs/other-blogs/mcafee-labs/revil-ransomware-uses-dll-sideloading"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/loader_win_revil_loader.yar#L4-L34"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		hash = "1fe9b489c25bb23b04d9996e8107671edee69bd6f6def2fe7ece38a0fb35f98e"
		hash = "50416e50797cf88a48d086e718c003e2d10c3847b1a251669d6f10f8d3546e03"
		hash = "66490c59cb9630b53fa3fa7125b5c9511afde38edab4459065938c1974229ca8"
		hash = "81d0c71f8b282076cd93fb6bb5bfd3932422d033109e2c92572fc49e4abc2471"
		hash = "aae6e388e774180bc3eb96dad5d5bfefd63d0eb7124d68b6991701936801f1c7"
		hash = "d55f983c994caa160ec63a59f6b4250fe67fb3e8c43a388aec60a4a6978e9f1e"
		hash = "dc6b0e8c1e9c113f0364e1c8370060dee3fcbe25b667ddeca7623a95cd21411f"
		hash = "df2d6ef0450660aaae62c429610b964949812df2da1c57646fc29aa51c3f031e"
		logic_hash = "15680c5e5d801d65e581869ad88d89863c8a51e3f94a3d2f37c02c5fd14df07f"
		score = 75
		quality = 80
		tags = ""
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$crypto = ".\\crypto\\" ascii
		$dropped_name1 = "MsMpEng.exe" wide
		$dropped_name2 = "mpsvc.dll" ascii

	condition:
		all of ( $dropped_name* ) and #crypto > 100 and for any i in ( 0 .. pe.number_of_resources -1 ) : ( hash.sha256 ( pe.resources [ i ] . offset , pe.resources [ i ] . length ) == "33bc14d231a4afaa18f06513766d5f69d8b88f1e697cd127d24fb4b72ad44c7a" )
}